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Manage Indoor Humidity with a Dehumidifier

In addition to being uncomfortable, humid indoor air also causes damage to your home and furnishings and promote the growth of mold and dust mites. Thankfully, purchasing a quality dehumidifier is a great way to solve the problem.

Controlling humidity levels is important. Relative humidity shouldn't exceed 40-50%. Learn the basics here, and determine if you have a household moisture problem.and if using a dehumidifier is right for you.

If you notice creaking floors, condensation developing on windows, or exacerbated allergy symptoms then your home's humidity levels may be too high.

Those living in hot, humid climates may also find that their homes provide the optimal environment for pests such as termites.

The chart below illustrates how humidity levels can affect your health and home:

Common Symptoms

High Humidity (Use Dehumidifier)

Low Humidity (Use Humidifier)

Allergic Reactions

Chapped Lips and Skin

Musty Odors

Respiratory Problems

Mold Growth

Static and Sparks

Stains on Ceilings and Walls

Scratchy Nose and Throat

Condensation on Windows and Mirrors

Damage to Electronic Equipment

Long Term Effects

Damage to Home and Furnishings

Damage to Home and Furnishings

Ongoing Allergies

Continued Respiratory Discomfort

Other Health Problems

All About Humidity Levels

Humidity is often associated with that muggy feeling you experience on a warm summer day. There are two forms of humidity: absolute humidity and relative humidity. Absolute humidity refers to the mass of water vapor divided by the mass of dry air in a volume of air at a given temperature. As such, the hotter the air, the more water it contains.

On the other hand, relative humidity refers to the ratio of the current absolute humidity to the highest possible absolute humidity. If an environment has 100% relative humidity, this means the air is saturated with water vapor and can hold no more moisture. This creates the possibility of rain.

Overall, humans are quite sensitive to humidity because the skin relies on air to get rid of moisture. Sweating is your body's way of keeping cool and maintaining its current temperature. This is why you feel hot and sweaty when humidity levels are high.

When there is low relative humidity, you feel much cooler than the actual temperature because sweat is quickly evaporating and cooling us off. In other words, if the temperature is 75° F with zero relative humidity, it will feel like it's 69° F. If relative humidity is 100%, it will feel like it's 80° F.

Recommended Relative Humidity Levels

According to the American Society of Heating, Refrigerating and Air Conditioning Engineers (ASHRAE) Standard Environmental Conditions for Human Occupancy, it is recommended that relative humidity be kept between 30% to 50% in the summer and 30% to 40% in the winter.

In order to measure humidity levels, you can purchase a small, inexpensive hygrometer. This device will confirm whether there is too little or too much humidity. Once you are aware of the humidity levels in your home, you can then decide if you need to take action.

To get an idea of the human perception of humidity, look to the chart below:

Human Perception

Relative Humidity at 90° F

Extremely Uncomfortable

62%

Very Humid and Uncomfortable

52 - 60%

Somewhat Uncomfortable for Most People

44 - 52%

Acceptable for Most; Some May Perceive it as the Upper Limit

37 - 46%

Comfortable

31 - 41%

Very Comfortable

31 - 37%

May Feel Slightly Dry to Some People

30%

Again, if your air is too dry, you can regulate moisture levels with a humidifier. However, if your air is too moist, a moisture removal system can help maintain the indoor relative humidity at the desired level, control musty odors, and protect furniture from water damage.

Dehumidifier Tip:

Excess humidity not only causes discomfort, but it can also add to your air conditioner's load. Therefore, a dehumidifier not only keeps you comfortable, but it can also help you save money on your AC bill.

What is a Dehumidifier?

Dehumidifiers are household appliances that help reduce the humidity levels in the air. There are primarily two types of humidifiers: desiccant and mechanical.

Mechanical Models are much more common. These units are like air conditioners, containing both hot and cold coils in the same box.

As the fan draws indoor air over the cold coil, the moisture is collected into a bucket. Dry air then passes through the hot coil to warm it back to its original temperature.

As a result, mechanical units raise the air temperature slightly, as opposed to air conditioners, which cool the air as it dehumidifies it.

This model is ideal for moderate to high humidity levels.

How to Choose the Best Dehumidifier for You

There are several factors to consider when shopping for a moisture removal system. Consider the size of the unit, dehumidification capacity, and safety features. Below is a list of some of the most common things to look for when choosing a moisture removal system and what it means to you.

Size: The size of a dehumidifying unit is generally based on the amount of moisture extracted from the air in 24 hours,. This is usually measured in pints. Purchase a larger capacity model over a smaller one because larger units can dehumidify more area in a shorter amount of time.

A model with a smaller capacity may run continuously and still not lower the humidity to proper levels. The AHAM, or Association of Home Appliance Manufacturers, recommends the following size guidelines:

Portability: If you're looking to move your unit from room to room, look for one that is compact, lightweight, and includes a carrying handle or rolling casters.

Built-In Humidistat: If you'd like to be able to adjust humidity levels, find an option with a humidistat. This feature will automatically turn the unit on/off depending on the humidity setting.

Automatic Shut-Off: This function will allow you to turn the unit on or off without having to unplug it. It also prevents overfilling when the storage tank is full.

Low Temperature Operation / Automatic Defrost: If you're using it in temperatures colder than 65° F, look for a unit that has an anti-frost sensor. You want ot make sure it will operate in cold temperatures. This prevents quick cycling and frost from accumulating on the sensor.

Storage Tank Capacity: Almost all types have storage tanks for the collected water. If you're not planning to purchase a model with a continuous drainage port, you'll have to empty the tank periodically.

Continuous Drainage: Models with a continuous drainage port eliminate the hassle of emptying a condensation tank. Simply attach a hose to the dehumidifier and the moisture will drain out through the hose.

Washable / Removable Air Filter: Units that have washable filters trap airborne dust and particles. If the filter is washable, this makes maintenance a breeze: simply pull out the filter; rinse it with mild soap and water; and put it back.

Brand: There are several brands available, so if you're loyal to a particular one, this may be something to consider.

Price: Many types can range from under $50 for mini units to $300 for basement models.

Dehumidifier Tip:

When it comes to dehumidifiers, placement is also important. If the unit has an air vent on top, it can be placed against the wall. If it doesn't, it will need to be placed away from walls and furniture for proper circulation.